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INCOME TAXES - Components of Net Deferred Income Tax Assets (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Deferred tax assets: |  |
Accrued liabilities and reserves | $ 38,820 | $ 39,232
Tax loss and credit carryforwards | 20,506 | 20,436
Capitalized research and development | 10,854 | 8,446
Inventory | 17,089 | 14,274
Lease obligations | 42,544 | 46,179
Other | 1,939 | 1,121
Deferred tax assets | 131,752 | 129,688
Deferred tax liabilities: |  |
Property, plant and equipment | (31,773) | (40,373)
Intangible assets | (11,961) | (43,487)
Right-of-use assets, net | (38,932) | (44,722)
Other | (5,820) | (6,609)
Deferred tax liabilities | (88,486) | (135,191)
Net deferred tax liability before valuation allowance | 43,266 | (5,503)
Valuation allowance | (20,854) | (20,517)
Net deferred tax assets | $ 22,412 |
Net deferred tax liability |  | $ (26,020)

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